Blackview freeze after one year usage.

My husband and I bought Blackview BV6300 Pro at end 2020. His phone started to freeze end 2021 and mine a month later. He is not currently using his Blackview after he had to factory reset. I refuse to do that with losing too much info. I am not happy with this product. It's got nothing to do with a virus or unnecessary apps. I make sure that I clean unnecessary folders, high resolution pics etc. Is this a bad batch device or bad software upgrades. It's just unlikely that both phones gave the same problems.